Welding Galvanized Material

[NCMau]

I have a fair amount of galvanized 1/4" angle iron stock that I have been using for years in different projects (arc welding). I guess I am following safe procedures by always welding outside with fans blowing.
My question is: how much of the coating you have grind off for an effective weld?
Also I noticed if I heat the metal with the torch for bending, the coating pops. Should I also grind the area before heating? I suppose that would minimize splashing.

 

[firedave19]

heating doesn't matter but should grind all coating off before welding and u should think of buying a respirator that smoke from galvanizing is really bad for ya

 

[RoyJackson]

If you get zinc poisoning (from the galvanized burning off...you'll have some difficultly breathing, IIRC), drink milk. That will alleviate it. You may want to go to the hospital...depends on how you feel.
However, grinding it off first is your best best (use a respirator for the dust). Grind about 2" or so from the weld joint. I doubt you'l be able to tell with your welding helmet on, but zinc burns with a green flame.

 

[NCMau]

heating doesn't matter but should grind all coating off before welding and u should think of buying a respirator that smoke from galvanizing is really bad for ya

Thanks. Respirator is a great additional precaution. I have one that I use for paint. Can I use the same one or should I get a different one.

 

[jake98]

Thanks. Respirator is a great additional precaution. I have one that I use for paint. Can I use the same one or should I get a different one.

Read the fine print, mine uses the same filter for both. I think you can weld right over the galv., just avoid the fumes. I'm not an authority on anything welding related tho.

 

[RoyJackson]

Read the fine print, mine uses the same filter for both. I think you can weld right over the galv., just avoid the fumes. I'm not an authority on anything welding related tho.

You can weld or (in my experience) braze without grinding the galvanized coating....that's why I know the zinc burns green.
However, then you will get the fumes.

 

[yomax4]

You can weld over the galvanised but it will be ugly, smokey and spattery. If you can't grind first, maybe use stick instead. Silicon Bronze is a faily good wire to use on galvanized or a gasless wire like NR211. The gases from the galvanized causes problems with the argon mix.

 

[Short Game]

Grinding the zinc produces both particulate and gasses. Hard to get a nice weld without grinding off the zinc. Easy to get a great braze, though. The zinc seems to make a great flux for bronze.

I don't like packing the respirator under my helmet, but it's worth it.

 

[crash325]

Grinding the zinc produces both particulate and gasses. Hard to get a nice weld without grinding off the zinc. Easy to get a great braze, though. The zinc seems to make a great flux for bronze.

Right on, zinc & brazing rod love each other.

Welding with stick or ? makes for a poor quality weld, usually week & pitted.

Fumes are poison, if you get enough that you can taste the zinc, drink lots & lots of milk. Work outside and wear a good mask.

 

[Soundguy]

I usually blow off with a torch then wire wheel, or grind off.. whatever I got handy..

that and weld outside with it / fan.. just try not to breathe welding fumes.. any of them.. zinc or not..

soundguy